The invention relates to a method for deforming a workpiece, such as a metal cylinder or plate, by means of a tool, in particular one or more forming rollers, wherein the workpiece and/or the tool are rotated about an axis relative to each other, the tool moves through one or more deforming curves and at least part of the workpiece is deformed. The invention furthermore relates to a forming machine for deforming a workpiece, which forming machine comprises a control unit.
Such a method and forming machine are known from European patent application No. 0 125 720. Said publication describes a forming machine comprising a control unit for controlling the movement of the forming roller. The control unit is connected to a detector for measuring the force exerted on the forming roller (by the workpiece) and to a detector for determining the position of the forming roller, whilst a memory is connected to the control unit for storing associated force/position values, and the control unit is adapted for controlling the movement of the forming roller in dependence on the force/position values that are stored in said memory.
Another example is described in WO 02/07907. Said publication relates to a method and a forming machine for deforming a hollow workpiece having at least one open end, wherein a first forming tool is placed into contact with the outer side of the workpiece and a second forming tool is placed in the cavity defined by the workpiece, into contact with the inner side of the workpiece, and the workpiece is deformed by means of tools.
In many cases, the length of the deformed portion of semi-manufactured products obtained by means of this type of methods and forming machines will be different from the length that is required or desirable in connection with further operations to which the semi-manufactured product is to be subjected. To obtain the required or desired length, an additional operation must be carried out in that case, for example cutting the edge (or edges) of said semi-manufactured products to size.